for fats and stuff.
for carbohydrates
for meat
for fats and stuff. for carbohydrates for meat
Human eats about 
= 
fat/dat or 
of normal food.
Athletic output:
For normal people divide by 2.
3W/kg for long periods of time.
Birds can manage better: 20W/kg (for 10 minutes) and 50W/kg in burst.
Bird muscles do 100W/kg muscle steady vs human 10 W/kg steady